Sighting apparatus for ordnance.



B. oLssou. SIGHTING APPARATUS FOR ORDNANOE,

APPLICATION FILED OCT. 21, 1908.

950,07 8. Patented Feb.v22, 1910.

3 SHEETS-SHEET l.

. APPLICATION FILED OCT. 21,1908.

Patent ed Feb. 22, 1910.

3 QHBETS-SEEET 2.

E. OLSSON.

SIGHTING APPARATUS FOR ORDNANCE.

APPLICATION FILED 00121, 1908.

950,078. Patented Feb. 22, 1910.

3 SHEETS-SHEET 3.

Irv/2116721577 vii Z" IS 01 wmew 63 M I ANDREW a (mum cm-PHOTU-LIWOGRAPNERS, WASNNGYDNO. a

EMIL OLSSON', 0F BO FORS, SWEDEN.

SIGHTING APPARATUS FOR ORDNANCE.

Specification of Letters Patent.

Patented Feb. 22, 1910.

Application filed October 21, 1908. I Serial No. 458,907.

To all whom it may concern:

Be it known that I, EMIL OLSSON, subject of Sweden, residing at Bofors,county of IVermland, Kingdom of Sweden, have invented new and usefulImprovements in Sighting Apparatus for Ordnance, of which the followingis a specification.

In ordnance of that kind where the gunbarrel, independently of the lineof sight can be adjusted for the elevation corresponding to the range,there arises, if, for some reason, the axle of the elevation-trunnionstakes up an inclined-position, after the piece has been sighted, a faultin the direction of the line of sight in relation to the barrelaxis,which said fault makes itself felt both in a horizontal and a verticaldirection, or, in other words, it can be divided into a horizontal and avertical component. In order to correct this fault, the line of sightmust, therefore, be swung in both a horizontal and a vertical directionrelatively to the gunbarrel. These rotations have hitherto been executedseparately, so that the line of sight has first been rotated around avertical axle until it has become parallel with the vertical-planethrough the barrel axis, and thereupon around a horizontal axle untilthe necessary elevation has been restored. It has, however, proved, thatit facilitates the sighting of the ordnance if both above-mentionedcorrections can be carried out simultaneously without demanding moreatten tion on the part of the sighter than a single one of them would doalone, and the present invention relates, therefore, to such a devicethat the line of sight on its being adjusted in a horizontal directionis simultaneously rotated so far in a vertical direction that the angleof elevation remains constant. This takes place in the simplest of waysthereby that the line of sight on correction taking place is made todescribe a part of a cone around an axle which is parallel with thebarrel-axis, but it should be evident that other ways too can lead tothe desired end.

The invention is illustrated in the accompanying drawings where Figure 1gives a lateral view of a form of construction of a piece of ordnance,constructed in'accordance with the present in vention; Figs. 2 and 3show detail-sections of said piece of ordnance along the lines IIII andIIIIII in Fig. 1, respectively; Fig. 4 shows a section along the lineIV-IV in Fig. 2, while Fig. 5 gives a schematic illustration of themethod of employing the invention. Fig. 6 is an enlarged detail view.

In Fig. 5, AA is the axis of the gunbarrel; and BB the axle of theelevationtrunnions, which is supposed to be horizontal, while thegun-barrel is elevated at a certain angle X. The mark is here supposed,for the sake of simplicity, to be on a level with the gun, so that thehorizonal projection aa of the axis will be directed direct toward themark. The line of sight CC should thus be parallel to the axis justmentioned, as the dimensions of the gun can, of course, be neglected incomparison with the range. If now, the trunnion-axle from one cause oranother, is inclined to the side at an angle ,8 to the position BB, itis clear that the axis will take up the position AA, so that its planeof rotation inclines at an angle of ,8 to the perpendicular. Thehorizontal projection aa of the axis inclines toward the line aa at anangle X the value of which is determined by the equation, tgX :tgXsin/3.As the l1ne of sight stands horizontally it will continue to remainparallel to the line aaand is only rotated up to the position CC, forwhich reason it will, together with the horizontal projection of theaxis, form the firstnamed angle X Simultaneously, however, the elevationof the gun has been decreased to the angle X, the value of which isdetermined by the equation: sinX sinXcosfi. In order to once more bringthe line of sight and the axis into correct reciprocal position, themethod has hitherto been adopted that the line of sight has first beenrotated in the horizontal plane at the angle X and the gun barrelthereupon elevated at the angle XX, the value of which is determined bythe help of tables. In the case of pieces of ordnance of the kind now inquestion, however, this method has proved to be a troublesome one, andthe present invention relates thereforeas was before mentioned by way ofintroduction to an arrangement of such a character that the line ofsight, on rotation to the side by hand at the angle X is simultaneouslyrotated downward at the angle X-X. While this is taking place, one orseveral others of the gunners can be engaged in once more adjusting theline of sight toward the mark by means of the heightand lateral-sightingapparatus; and while so doing, can be perfectly independent of the onewho is occupied with the correction for the trunnion-slope. Apart fromthe sighting movements now spoken of, which are not illustrated in thefigure, the line of sight shall thus be rotated to the position CC,which is parallel to the vertical plane through the axis AA, with whichit forms the angle X. In the simplest way this takes place, as wasmentioned at the beginning, by the line of sight having to describe acone around the line DG, which is parallel to the axis, and thisprinciple is made the basis of the form'of construction of the inventionillustrated in Figs. 14, and now about to be described.

To the cradle 1, which carries the gunbarrel 2 there is firmly attacheda sidewardly projecting bracket 3, which is fork shaped at the end andprovided with bearings for a rotatable shaft 4, which is parallel to theaxis of the gun-barrel. This shaft has a frame-shaped part 4, in whichan arm 5 which supports the sighting device is journaled by means ofpins 6, 7, whose middle line coincides with that of theelevationtrunnions, when both pairs of pins are horizontal. In thedrawing there is shown only a telescope-sight, but there may be providedboth sight and dispart sight on the arm 5 with the line of sightparallel to the optical axis of the telescope.

On the axle 4 there is displaceably, but not rotatably, arranged asleeve 9 to which there is rotatably, but not displaceably, attachedanother sleeve 10. Each of these sleeves is provided with an arm 9 and10 respectively, projecting downward, each of said arms supports a pin 8and 11 respectively, the middle line of said pins being in the sameplane perpendicular to the axle 4 at equal distances from said axle. Onthese said pins there are rotatably journaled the ends of two links 8and 11 respectively, which are equal in length and the other ends ofwhich are firmly linked to the lower end of the arm 5 and to an arm 12respectively, which latter is rotatably journaled in theelevation-trunnion and is attached to the height sighting mechanism. Thelower fork of the arm 5, reckoned from the trunnions 6 and 7 to thepoint of attachment to the link 8, is just as long as the arm 12reckoned from the gun trunnion to the point of attachment to the link11.

The elevation is read off by means of a graduated scale 20, whichisfirmly attached by means of a toothed gear 19 to a shaft j ournaled ina mantle 18 firmly attached to the arm 5. The toothed gear 19 engages ina toothed segment 21 firmly attached to the shaft 4. In order to adjustthe pins 6, 7

horizontally, the following device is used.

One of the arms of the bracket 3 is prolonged downward to an arm 13 inwhich there is journaled a screw 14 which engages in a toothed segment16, which, by means of an arm 17 is firmly attached to the shaft 4, sothat this said axle together. with the pins 6, 7 can thus be rotated byturning the screw 14.

hen the piece ofordnance is elevated independently of the line of sight,the shaft 4 accompanies the motion of the gun-barrel, while the arm 12.at the same time stands still. The sleeves 9 and 10 are pushed backwardon the shaft 4, but the arm 5 with the sighting apparatus remainsunchanged in position owing to the connection of the arm 5 with the arm12 by means of the links 8 and 11 and the sleeves 9 and 10.

lVhatever the angle may be between the line of sight and the axis of thepiece of ordnance (or the middle line of the axle 4, respectively), theline of sight can, by means of the screw 14, be rotated about thelastmentioned middle line without altering the angle between this middleline and the line of sight. In performing above-mentioned movement theline of sight thus describes a cone about said middle line.

If the piece of ordnance is directed toward a mark and is elevated for acorresponding range (which range is read off on the scale 20) and theaxle of the elevation-trunnions is thereupon given a slope, it is merelynecessary to turn the screw 14 until the pins 6 and 7 become horizontaland the bubble in the gunners level on the arm 5 occupies its centralpoint, then the position of the line of sight in respect to the axis ofthe piece is, again, the correct one both in respect of heightandlateral direction.

It is to be observed, that the before-described device for correctingthe line of sight is claimed only in combination with ordnance of theknown kind, where the sighting toward the mark and the elevating corresponding to the range can be executed simultaneously and independentlyof each other thereby, that in turning one hand-wheel (thesighting-wheel) the sighting instrument and the barrel follow eachother, so that the angle between these two parts remains constant, whilein turning another hand-wheel (the elevating wheel) only the barrel isswung, so that the angle between the line of sight and the barrel isaltered.

Claim.

In combination with a gun and its cradle, of a sighting devicecomprising a bracket mounted on the cradle, a shaft rotatably connectingthe other sleeve with the carrier, and means for rotating the shaft.

In witness whereof I have hereunto set my hand in presence of twoWitnesses.

EMIL OLSSON.

Witnesses BIRGER NORDFELDT, HJALMAR ZETURSTROM.

